1. Field of the Invention
The present invention relates to functioning optical lenses having optical functions such as an antiglare function, a dimming function, and a polarizing function. It also relates to methods of producing the functioning optical lenses. Such functioning optical lenses may be used, for example, antiglare lenses, photochromic lenses, and polarizing lenses, for example, in goggles and sunglasses.
2. Description of the Related Art
Functioning optical lenses are currently widely used and have the function of, for example, absorbing light at specific wavelengths or preventing glare caused typically by reflected light. Of these functioning optical lenses, polarizing lenses have polarizing functions and are used as sunglass lenses for preventing diffuse reflection. Japanese Unexamined Patent Application Publication (JP-A) No. 2002-90529, for example, discloses a polarizing composite lens. This lens is prepared by laminating an optically transparent nylon (polyamide) sheet onto one side of a polarizer plate with the interposition of an acrylic adhesive to yield an intermediate composite, curving the intermediate composite, and thermally fusing the optically transparent nylon (polyamide) sheet with a resin of the same composition, in which the polarizer plate includes a polarizing sheet sandwiched between two triacetyl cellulose (cellulose triacetate; TAC) layers. This technique, however, is disadvantageous in production efficiency, because such a nylon resin may not be thermally fused with TAC, and an extra nylon sheet should be arranged between the two layers.
Japanese Unexamined Patent Application Publication (JP-A) No. 2002-258220 discloses a composite molded article. This composite molded article includes a sheet polarizer, an adhesive, and a polycarbonate layer arranged in this order. The polycarbonate layer is prepared by injection molding. The sheet polarizer includes a polycarbonate (PC) protective layer, a polarizing film, and a polycarbonate stretched film. This composite molded article can be produced by a process including less steps and can be used as a polarizing lens for spectacle glasses as a result of polishing. The composite molded article is, however, poor in processability. This is because, when such a polarizing lens including a polycarbonate is processed into frame-less spectacle glasses by forming holes directly in the lens, the lens is susceptible to cracking or breaking. Polycarbonates may often undergo deformation upon injection molding. The resulting lenses containing a polycarbonate may be corroded when they are processed into spectacle glasses, because plasticizers, such as diethyl phthalate, bleed out and corrode the polycarbonate. In addition, more light-weight optical lenses are demanded.